The present invention concerns a compressor of air or any other gas for a low cost price, in which the primary energy used in the compression cycle is not mechanical or electrical energy as in most compressors, but thermal energy directly; this compressor contains no moving parts subject to wear and tear, and the losses of energy due to friction and the surplus heat from the cold source of the cycle may be recovered and re-used in the compression cycle or to generate pressurized steam which, when mixed with the compressed gas, increases its flow rate.
This device is intended for compression or partial vacuum application of any industrial gas, but its thermal cycle makes it particularly suitable for use in construction of high efficiency thermo-energy plants, in construction of energy economising systems such as mechanical recompression of steam, or for the recovery and reconversion of residual thermal energy.
In the current state of the technology, compressors consist of devices in which the gas compression energy is supplied in the form of mechanical energy: volumetric compressors, centrifugal or axial compressors, etc., or compressors using the potential or kinetic energy of another entraining gas, which is also a form of mechanical energy: ejectors.
In addition, the research report mentions devices of the “ejector” type in which the origin of the mechanical compression energy is the kinetic energy of a entraining gas or liquid, which is the case with patents No. BE537693, GB928661, and EP0514914, or is a device relating solely to mixes of gases without the presence of liquid, which is the case with U.S. Pat. No. 3,915,222, the operation of which is doubtful; the operational principles themselves and the elements constituting these devices cannot be compared to the device forming the subject of the present patent, in which the compression energy is neither mechanical energy or the kinetic energy of a entraining fluid, but solely thermal energy, with indispensable mixing of the gas for compression and a liquid evaporation of which allows the heat to be taken from the cycle's cold source to be absorbed.
Compressors in the current state of the technology require substantial maintenance due to the mechanical friction and the wear and tear which result, and have low energy efficiency levels, or even very low ones in the case of ejectors, due essentially:
To the multiple conversions of energy in the facilities used: Thermal motors or Turbines to convert thermal energy into mechanical or electrical energy, possibly alternators and electric motors to retransform the electrical energy into mechanical energy, and lastly compressors to transfer the mechanical energy to the gas for compression,
To the relatively low temperatures used in the first transformation of thermal energy into mechanical energy in power stations,
To the reheating of the gas for compression when it is compressed, which inevitably means that the compression is far from being adiabatic,
To the mechanical friction and the losses of kinetic energy of the gas for compression,
To the non-recovery, in the total cycle, of the thermal energies resulting from the compression, of the losses by friction, and of the cold source of the motor or turbine,
To mechanical wear and tear,
To deposits and soilings on the air compressors: even frequent washings of the gas turbine compressors can only attenuate the effect of these soilings.